Devices for generating two dimensional (2D) video data are known, for example video servers, broadcasters, or authoring devices. Currently 3D enhanced devices for providing three dimensional (3D) image data are being proposed. Similarly video devices for processing display 3D video data are being proposed, like players for optical disc (e.g. Blu-ray Disc; BD) or set top boxes which render received digital video signals. The 3D video device is to be coupled to a 3D display device like a TV set or monitor. Video data is transferred from the source device via a suitable interface, preferably a high-speed digital interface like HDMI.
In addition to 3D content, such as 3D movies or TV broadcasts, additional, auxiliary 2D video data may be displayed, for example a menu, news flash or other announcements. Furthermore, in practice a user may select 3D video material or 2D video material at will from various sources. Moreover, the user may apply a setting to force displaying in a 2D mode, even when 3D video material is available.
Document WO2009/077929 describes approaches that could be taken to transition between 2D and 3D. A 3D video signal has video information and associated playback information, the video information and associated playback information being organized according to a playback format. The video information comprises a primary video stream for 2D display, and an additional information stream for enabling 3D display. The associated playback information comprises display information indicating the types of display possible. The display information is processed at the receiver to determine that both 2D display and 3D display are possible. A playback mode is set determining whether the video information should be displayed in 2D or 3D mode.